Honda gxv390 engine

[john2189]

I would like to install battery starter to this motor. I have a gx340 motor I took the flywheel off for the ring gear and comparing it to the one I took off, the magnet that fires the coil is off about 1/4”. Would they have changed the timing for battery start? Would 1/4” make that much difference?

[Jim Becker]

More likely the timing is different between the 340 and 390 rather than being different for an electric start. Note that most specs are the same between the two models, but somehow the 390 produces more power and max torque is at a higher speed. Changes in cam and ignition timing seem like probably differences. I don't think I would try to mix cam profile of one model with the ignition timing of the other.

Maybe you can move the magnet?

[john2189]

Thanks Jim, that’s a possibility. Thought about machining the original for the ring gear, but not enough material to do that.

[john2189]

Ok I put the flywheel on and pull started it. I can’t tell any difference. It will run full throttle with blades on, sounds good. Now to buy a starter. 

thanks for your input 
John